The Universal Firmware Update feature is relevant for IGEL OS 11 devices and earlier, not for IGEL OS 12 devices.
The UMS initiates a TCP connection to port 443 at fwus.igel.com. The IGEL download server will send an answer containing a list of download links that enable the UMS to download the desired firmware.
Direct Connection
The following figure illustrates the communication between the UMS server and the IGEL download servers:
Via Proxy
When a proxy is positioned between the UMS and the IGEL download servers, the port on which the proxy is listening must be specified under UMS Administration > Global Configuration > Proxy Server.